to the bitter end
US /tə ðə ˈbɪtər ɛnd/
UK /tə ðə ˈbɪtər ɛnd/

1.
끝까지, 최후까지
until a struggle or unpleasant experience is completely finished, despite difficulties or suffering
:
•
They fought to the bitter end, refusing to surrender.
그들은 항복을 거부하고 끝까지 싸웠다.
•
She decided to stick with the project to the bitter end, even though it was very challenging.
그녀는 매우 힘들었지만 프로젝트를 끝까지 고수하기로 결정했다.